Green’s Dictionary of Slang

(Aus.) a heart attack.

1999		Google Groups: aus.talk.ltuae 25 Jan. 🌐 Sheesh, don’t give me a heartie, ok? Life’s tough enough!
2008		K. Howell Darkest Hour 207: ‘Dude fell on his scone, had a heartie, officers did CPR till the ambos got there, and they took him to hospital but he was dead’.
2016		Adventure Rider 11 Nov. 🌐 phone just had a heartie.